1. Field of the Invention
This invention relates to a tape drive device for supplying and taking up a tape-shaped information recording and reproducing medium such as a magnetic tape or a film.
2. Description of the Prior Art
It is strongly demanded to reduce the volume, thickness and weight of information recording and reproducing apparatus, for example, cassette tape recorders, video tape recorders, 8-mm cinecameras, etc. for the purpose of saving the required materials and also for the purpose of improving the portability.
A tape-shaped information recording and reproducing medium such as a magnetic tape or a film (referred to hereinafter merely as a tape) used in these information recording and reproducing apparatus is generally driven at a predetermined constant speed by a capstan and a pinch roller of a tape drive device. A hub for a take-up reel and a hub for a supply reel are provided to take up the tape travelling at the constant speed and to supply the tape at a high speed. In another type of such a tape drive device, the capstan and the pinch roller are eliminated, and the pair of reel hubs used for the take-up and supply of the tape are utilized to feed the tape at the constant speed and to feed the tape at the high speed. In any one of the known tape drive devices, a motor is provided as a source of power for driving the capstan or the reel hub pair. However, due to the fact that the motor employed hitherto as the drive power source has a considerable height and a considerable volume, and various mechanisms including a power transmission mechanism including a belt or the like, a reel hub slip mechanism and an actuating mechanism performing constant-speed feeding, fast forwarding, rewinding and other functions are also required for the tape drive, these parts occupy very large proportions of the volume, height and weight of the information recording and reproducing apparatus. It has therefore been unable to meet the demand for the reductions in the volume, thickness and weight of the information recording and reproducing apparatus.